This monument was created to preserve a grove of redwood trees. PresidentTheodore Roosevelt declared the area a national monument in 1908. It had been donated by a congressman, William Kent, and his wife. They purchased 295 acres for $45,000 in 1905. It was Kent's idea to name it after John Muir, a famous conservationist.

The forest is mainly comprised of redwoods, but there are also Douglas-fir, big-leaf maple, tanbark oak, red alders, buckeyes, and bay-laurel. The park offers trails that meander through the forest.